Analysis of passive films of advanced tooling alloys by synchrotron X-ray photoelectron techniques
| Reference number | |
| Coordinator | Kungliga Tekniska Högskolan - Department of Chemistry |
| Funding from Vinnova | SEK 500 000 |
| Project duration | November 2020 - May 2022 |
| Status | Completed |
| Venture | Research infrastructure - utilisation and collaboration |
| Call | Industrial pilot projects for utilisation of large-scale infrastructures for neutron and photon based techniques – 2020 |
| End-of-project report | 2020-03778 _Uddeholms.pdf (pdf, 630 kB) |
Important results from the project
The aim of the project is to utilize synchrotron techniques to study passive film on tooling alloy and effect of heat treatment. We performed electrochemical measurement to evaluate corrosion resistance, and surface analyses, i.e., ambient pressure XPS and electrochemical XPS (after anodic polarisation). The results reveal the importance of hydroxides in the passive film and changes of the film due to anodic polarisation as well as the heat treatment, which greatly improved our understanding of the corrosion resistance of the tooling alloy and the effect of heat treatment.
Expected long term effects
The electrochemical measurement provided information about general corrosion behaviour of the tooling alloy and the effect of heat treatment, while the surface analyses, both ex-situ and in-situ XPS measurements, reveal the chemical composition of the passive film, as well as the changes of the passive film due to the heat treatment, which greatly improved our understanding of the corrosion resistance of the tooling alloy and the effect of heat treatment. The results provide explanation of the corrosion resistance, and also can help the company to optimise the heat treatment.
Approach and implementation
The group at KTH has expertise in corrosion, electrochemistry and surface analysis, while Uddeholm company has expertise in processing and microstructure of tooling alloys but lack of knowledge of the passive film on the alloys. In this project, electrochemical measurements were performed at KTH, and synchrotron XPS analyses of the passive film was done at the HIPPIE beam line at MAX IV in collaboration with synchrotron experts. The collaboration has been very successful and demonstrated the possibilities for industry to utilize advanced synchrotron techniques in their R&D work.